316 MBTALLUEGT OF IRON AND. STEEL.
elimination, but this will hardly apply to. the results given on pages-59 and 61* showing two weeks' working and the' composition of fifty-five heats. Of these the sulphur content was as follows:
" , . 7 heats between- .040 and .049 per cent.
20 " " .050' " .059
21 " " .060 " .069 : , 3 " " .070 " .079
3 " " .080 " .089
, .1 heat ... .. .090
If sum" dent : time had been allowed for the elimination of. sul-jphur, , anal if during all this time the slag had been more basic, more viscous and more voluminous, the time would have been increased, and the amount, of fuel greater. The iron was melted in a cupola, and this raised the sulphur, but a blast furnace could not be relied upon to furnish a better iron than was -used.
The Talbot process has an advantage in the greater output from a given ground area, a vital matter in a constricted city works. It is also of value where the open-hearth furnaces must run almost wholly on pig-iron containing a high percentage of phosphorus, /as £tt Frodingham, England.
SEQ. Xlld. The Bertrand Thiel process. There has been developed at Ifladno, in Bohemia, a system of handling phosphoric pig-iron. There were two open-hearth furnaces- on- different levels, making it possible to tap from one furnace into the other by means of a runner. The higher furnace is used to remove the silicon, part of the carbon and most of the phosphorus, while the second completes, the,1 process. Many years ago, when the practice had not been reduced to precision, Mr. Bertrand piiblishedf the results of ,. twelve heats,, which show that the metal was in the first furnace an- average off 4 hours and 50 minutes, and in the second 2 hours and 'SO minutes. ; ' i , ; ' ;
;; The proportions of pig-iron and serap are unimportant^ but -it" -is considered best to charge-mostly pig-iron in the first furnace, using sufficient, ore to give a good reaction and, oxidize the metalloids,, and to change some, scrap in the second furnace. ;The sj:ock in the second furnace is partly melted when the steel runs, to, it, .and. tiiere is, a quick- and violent reaction. Care is taken to allow no slag to run to the second furnace,; and, the phosphorus, which has been elimi-
: *.ioc.ct*. : ' "'' * Journal I. and S. L, Vol. 1, 1897.